Skip PaintPhaseFloat if no floats in a layer

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 1449 matching lines @@
     LayoutRect rect = visualOverflowRect();
     LayoutView* layoutView = view();
     while (layoutView->frame()->ownerLayoutObject())
         layoutView = layoutView->frame()->ownerLayoutObject()->view();
     mapToVisibleRectInAncestorSpace(layoutView, rect, nullptr);
     return rect.intersects(LayoutRect(layoutView->frameView()->scrollableArea()->visibleContentRectDouble()));
 }
 
 PaintInvalidationReason LayoutBox::invalidatePaintIfNeeded(PaintInvalidationState& paintInvalidationState, const LayoutBoxModelObject& paintInvalidationContainer)
 {
+    if (isFloating())
+        paintInvalidationState.enclosingSelfPaintingLayer(*this).setNeedsPaintPhaseFloat();
+
     PaintInvalidationReason fullInvalidationReason = fullPaintInvalidationReason();
     // If the current paint invalidation reason is PaintInvalidationDelayedFull, then this paint invalidation can delayed if the
     // LayoutBox in question is not on-screen. The logic to decide whether this is appropriate exists at the site of the original
     // paint invalidation that chose PaintInvalidationDelayedFull.
     if (fullInvalidationReason == PaintInvalidationDelayedFull) {
         if (!intersectsVisibleViewport())
             return PaintInvalidationDelayedFull;
 
         // Reset state back to regular full paint invalidation if the object is onscreen.
         setShouldDoFullPaintInvalidation(PaintInvalidationFull);
@@ skipping 3424 matching lines @@
 }
 
 void LayoutBox::clearPreviousPaintInvalidationRects()
 {
     LayoutBoxModelObject::clearPreviousPaintInvalidationRects();
     if (PaintLayerScrollableArea* scrollableArea = this->scrollableArea())
         scrollableArea->clearPreviousPaintInvalidationRects();
 }
 
 } // namespace blink